, Volume 52, Issue 2, pp 137–144 | Cite as

Neurochemical investigations of the interaction of N,N-dimethyltryptamine with the dopaminergic system in rat brain

  • P. C. Waldmeier
  • L. Maître
Animal Studies


N,N-dimethyltryptamine (DMT) is a psychotomimetic indolealkylamine that has been suspected of being an endogenous causal factor in the aetiology of schizophrenia. Some aspects of its interaction with the dopaminergic system of the rat brain have been studied neurochemically, and comparisons have been made with the effects of d-amphetamine and apomorphine. In contrast to these two compounds, DMT has proved to be a potent, but short-acting MAO inhibitor with a rather selective effect on MAO A (serotonin-deaminating MAO).

Like classical MAO inhibitors, DMT also greatly increases the accumulation of 3H-dopamine plus 3H-3-methoxytyramine newly formed from 3H-Dopa. Amphetamine and apomorphine have no comparable effect.

Striatal levels of 3,4-dihydroxyphenylacetic acid are more efficiently lowered by DMT than those of homovanillic acid. the reverse has been observed with apomorphine, whereas amphetamine increases the concentrations of homovanillic acid and decreases those of 3,4-dihydroxyphenylacetic acid.

Thus, in addition to its MAO inhibitory action, DMT probably also possesses dopamine-releasing effects. Both these properties could result in an indirect dopaminomimetic activity of DMT. It may be assumed, therefore, that the psychotomimetic activity of this compound is not noly linked to its effects on cerebral serotonergic mechanisms, but to a combination of these with an indirect dopaminergic stimulant activity.

Key words

Dimethyltryptamine Monoamine oxidase inhibition Dopamine metabolism Homovanillic acid 3,4-Dihydroxyphenylacetic acid Dopamine release 


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Copyright information

© Springer-Verlag 1977

Authors and Affiliations

  • P. C. Waldmeier
    • 1
  • L. Maître
    • 1
  1. 1.Department Forschung, Division PharmaCiba-Geigy AGBaselSwitzerland

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